Art. 18. The Controlling Authority shall be chosen by and be responsible to a Commission of Control appointed to any State which desires to avail itself of the protection hereby afforded to safety zones by the President of the Permanent Court of International Justice, and may be so appointed in time of peace as well as in time of war. Such Commission of Control shall consist of not less than three nationals of non-belligerent States, and shall be accorded every facility for the carrying out of its duties by the Government of the State to which it is appointed, and shall enjoy diplomatic privileges, but shall not interfere with the territorial sovereignty of such State.